As a system for remote-controlling a mobile robot, a technique taught by Patent Reference 1 can be given as an example. In the technique described in Patent Reference 1, when the communication between the mobile robot and an external terminal which is a transmitting source of motion command is failed, the mobile robot is configured to be controlled to move to a position which enables it to communicate with the external terminal based on a communication history, such that the mobile robot moves only within a predetermined area.    Patent Reference 1: Japanese Laid-Open Patent Application No. 2002-273677 (paragraph 0007, etc.)